Artificial Intelligence / Unit 3 AI 0150 worked example, 60 to 90 seconds
The Stall Duel, Scored
The idea
One worked market-stall duel shows minimax scoring with numbers instead of wins and losses.
In practice
You choose one of three stall spots — Fountain, Gate, or Market Hall; a rival selling the same pastries then sets up in response, and their gain is your loss. Scouting gives your profit, in tens of dollars, for each pairing. Fountain's three outcomes: 4, 9, 6. Gate's: 8, 2, 11. Hall's: 7, 5, 10. Score backward. Each rival-fork takes its minimum — the rival picks whatever hurts you most — so Fountain becomes 4, Gate becomes 2, Hall becomes 5. Your fork takes the maximum of 4, 2, and 5: choose Market Hall, and the duel's minimax value is 5 — fifty dollars guaranteed whatever the rival does, and fifty is also all the rival will ever concede.
Where people slip
Gate dangled the day's biggest number, 11, and Gate is the worst choice — its guarantee is 2.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Something wrong in this lesson? Flag it · Sources for Artificial Intelligence